drm/radeon: always set GEM function pointer

Make sure to always set the GEM function pointer even for in kernel
allocations. This fixes a NULL pointer deref caused by switching to GEM
references.
Signed-off-by: Christian König <christian.koenig@amd.com>
Fixes: fd69ef05 ("drm/radeon: use GEM references instead of TTMs")
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 01b64bc063d014641631867a7e0edd8ac55282d4)

drivers/gpu/drm/radeon/radeon_gem.c

@@ -44,8 +44,6 @@ struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj);
 int radeon_gem_prime_pin(struct drm_gem_object *obj);
 void radeon_gem_prime_unpin(struct drm_gem_object *obj);
 
-const struct drm_gem_object_funcs radeon_gem_object_funcs;
-
 static vm_fault_t radeon_gem_fault(struct vm_fault *vmf)
 {
 	struct ttm_buffer_object *bo = vmf->vma->vm_private_data;
@@ -132,7 +130,6 @@ int radeon_gem_object_create(struct radeon_device *rdev, unsigned long size,
 		return r;
 	}
 	*obj = &robj->tbo.base;
-	(*obj)->funcs = &radeon_gem_object_funcs;
 	robj->pid = task_pid_nr(current);
 
 	mutex_lock(&rdev->gem.mutex);

drivers/gpu/drm/radeon/radeon_object.c

@@ -151,6 +151,7 @@ int radeon_bo_create(struct radeon_device *rdev,
 	if (bo == NULL)
 		return -ENOMEM;
 	drm_gem_private_object_init(rdev_to_drm(rdev), &bo->tbo.base, size);
+	bo->tbo.base.funcs = &radeon_gem_object_funcs;
 	bo->rdev = rdev;
 	bo->surface_reg = -1;
 	INIT_LIST_HEAD(&bo->list);